Science and Practice in Farm Cultivation

by James Buckman

CHAPTER XLI.

ON THE KINDS OF TIMBER BEST ADAPTED FOR DIFFERENT SITUATIONS.

That the growth and quality of timber will be influenced by the nature of the soil is a matter so well understood that it would scarcely require to be treated of in this place, if we did not daily see examples of planting in which all laws of growth have been set at defiance; still, occasionally, experience has lent her aid and produced some satisfactory results; and, as an exemplification of our meaning, and as showing the influence of geological position upon planting, we would direct attention to the following section:—

ALICE HOLT FOREST.

4. Chalk. 3. Chalk Marl. 2. Upper G. S. 1. Gault Clay.

Here we have the oak—of both varieties known to planters, to be hereafter described—flourishing most luxuriantly on the stiff soil of the gault; the chalk-marl, upper green sand, and gault—the two latter only partially—being engaged in hop cultivation. The green sand surrounding the forest is mostly devoted to the growth of larch or spruce, the thinnings of which are used for hop-poles and the larger trees are left as timber-belts; whilst the beech will be found to favour the chalk. Hops and other cultivated plants flourish according to geological position.

That the geology of a district affects vegetation mainly, according to the mechanical and chemical structure of its individual rocks and the climate in which they are situate, is quite true; and yet the following table will show that different formations favour the growth of trees upon other conditions than those named.

Choosing figures to represent relative values, the annexed table is intended to show the amount of influence exercised by certain geological rocks in the growth of different fruit and forest trees met with in England.

				No.	Rocks.	Apple.	Pear.	Oak.	Elm.	Beech.	Firs.
Cretaceous Rocks.	-			1	Chalk	2	0	2	4	8	5
				2	Green Sands	3	1	3	7	0	3
				3	Gault	4	1	6	6	0	0
Jurassique Rocks.	-			4	Oxford Clay	6	0	10	8	0	1
				5	Oolite Freestone	2	0	1	4	10	5
				6	Lias	10	3	5	10	0	1
				7	New Red Sandstone	8	10	7	12	0	2
				8	Mountain Limestone	1	0	2	2	3	1
				9	Old Red Sandstone	15	8	8	10	0	1

These figures may serve to express—although roughly—the capacities of different formations for the production of fruit and forest trees, and it may be curious to note that, while the chalk and the oolite freestones, both composed of carbonate of lime, offer a remarkable agreement in point of dendrological productions, the mountain limestone, also consisting of carbonate of lime, affords very different results; here, no doubt, the different kinds of scenery presented by the rocks themselves have a decided influence on the general results.

Much, however, of any geological influence in the growth of trees must depend upon the material rather than upon the position of the rocks forming the subsoil upon which they occur, and thus it may be expected that clays, limestones, and sands, and different mixtures of these, will each favour the growth of a peculiar spontaneous or native vegetation; so that, if we looked to a larger list of trees and coupled it with lists of herbaceous plants, we might make out even a stronger case, either for the effects of geological or lithological conditions; but enough has been said to point out that various trees naturally affect one position more than another, and so they succeed as the results of planting and cultivation in one kind of soil in preference to another, and it may be laid down as a rule, that pomaceous fruits and hard-wooded trees, as oak and elm, only flourish in strong soils, though they may be imperfectly grown in all soils, whilst soft-wooded trees, as beech, lime, and the coniferæ, succeed best in lighter soils; hence, then, the planter who would try to grow vigorous oak on sandbeds would be disappointed, and while beech is the “weed” of the Cotteswold oolite, whoever tries to grow an orchard upon the freestone rocks is sure to meet with disappointment.

As regards forest trees we shall, for the most part, confine our remarks to those of the following list, as, although of recent years many new genera and species have been introduced, they are not yet in general cultivation even for ornamental purposes, much less as a source of profit.

LIST OF NATIVE OR NATURALIZED FOREST TREES.
Oak		-	Our more common timber trees used in buildings, furniture, cooperage, turnery, &c.
Chestnut
Walnut
Elm
Ash
Beech
Birch		-	Employed in furniture, turnery, &c. The British Coniferæ are not used for timber, except for fencing and other common purposes.
Larch
Spruce
Scotch Fir
Poplar
Plane		-	Employed for turnery, picture-frames, and occasional useful purposes.
Mountain Ash
Maple
Lime

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